There are a number of inexpensive CAD packages for the Macintosh available for under $250. Challenger Software's Mac3D is powerful and easy to use, and allows two-dimensional objects to be revolved into 3D entities. Version 2.1 adds color and on-line help. B. Knick Drafting's $219 MacPerspective creates wire-frame perspectives from dimensional drawings which can be entered as either relative or absolute coordinates. LionsHead Software Inc's $99 Pentagon CAD offers a general-purpose CAD environment at a very reasonable price. Alternative Enterprises' $55 Housebuilder is a set of MacPaint documents from which house plans can be developed using a standard paint application.